Delphi and MobilEye are teaming up to build a bolt-on self-driving system, adding to the list of companies that think it’s the future of automobile autonomy.

While many large technology and car manufacturers are building self-driving cars from the ground up, an increasing number of off-the-shelf systems will allow plenty of other models to take to the road without a driver.

The latest such project is a newly announced partnership between the GM tech spinoff Delphi Automotive and Israeli machine vision company Mobileye. Both companies are no stranger to self-driving car technology: they both supply sensors and software to big-name automakers, including the technology behind Volvo’s vehicle detection systems and, until recently, Tesla’s Autopilot.

But while both companies work closely with car manufacturers—Mobileye is working with BMW to put an autonomous car on the road by 2021, for instance—other large automakers, such as Ford, are building systems in-house. Now, according to the Wall Street Journal, the pair plans to invest “several hundred million dollars” in developing an off-the-shelf autonomous driving system, presumably for use by automakers who don’t have the capacity or inclination for such research and development.

The collaboration promises to demonstrate a system that will allow cars to autonomously navigate challenging road conditions—such as roundabouts or turns across multiple traffic lanes—as soon as January. The final product, though, will be longer in the making, with systems claimed to be available from 2019.

Delphi and Mobileye aren’t the only companies creating plug-and-play systems for autonomous vehicles. University of Oxford spin-out Oxbotica has developed a new software system that can make any vehicle driverless—using machine learning to provide the intelligence required to ingest data from sensors, understand surroundings, then decide how to move. It claims to already be working with auto manufacturers.

Meanwhile, startups such as Cruise Automation and Otto have been developing combinations of sensors and artificial intelligence software that allow them to turn everything from big rigs to humble family cars into self-driving vehicles. Both have been acquired recently as well—by General Motors and Uber, respectively.

But there’s something to be learned from another driverless car startup, Comma.ai, about a potential selling point of products that MobilEye and Delphi—and perhaps Oxbotica—intend to create. Set up by George Hotz, who became famous when he hacked the the iPhone in 2007, Comma.ai has demonstrated an autonomy system that uses machine learning and $1,000 of hardware to control a vehicle. The project has received criticism, but it goes a long way toward showing that, with the correct software and well-chosen sensors, off-the-shelf autonomy features could be an affordable upgrade for new cars.